


Horny

by LanxBorealis



Series: BAP AU [1]
Category: Gravity Falls
Genre: Alternate Universe, BAP AU, Bad Boy Bill Cipher, Bear Dipper Pines, Bill Cipher Is Weird, Demons, Established Relationship, M/M, Making Out, Overweight Dipper Pines, Yes the title is a pun sue me, i suggest not reading this, note that this entire series is tadbilldip, so if you dont like that ot3
Language: English
Status: Completed
Published: 2017-06-29
Updated: 2017-06-29
Packaged: 2018-11-21 04:55:13
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,260
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11350299
Author URL: https://archiveofourown.org/users/LanxBorealis/pseuds/LanxBorealis
Summary: During the most inopportune time, Dipper finds out the truth of exactly what Bill Cipher really is.[Prequel to "Bill's Husband"]





	Horny

**Author's Note:**

> Even tho this is a prequel to "Bill's Husband," it would be a good idea to read that first before this. This is a prequel in events only, but that fic kinda goes into more detail about their relationship then here I guess. At least for now. This will probably get a prequel later in the future on how Dipper met Bill in the first place. We'll see.
> 
> Also, tho this fic is tagged as being BillDip only, this entire series is TadBillDip. Since Tad doesn't appear in this at all, I didn't put him in the tags, but if you don't like TadBillDip, I would suggest not reading this.

Dipper gasped, his arms around Bill tightening as Bill prodded Dipper's lips open with his oddly pointed and long tongue.

Dipper and Bill's earlier date had seemed to fly right on by Dipper, and into the approaching twilight. Though Dipper knew many people wouldn't _exactly_ call a walk in the park and going to the store to pick up groceries a date, Dipper wasn't many people, and he couldn't help but treasure the time he spent with Bill.

Weird, eccentric, and somehow classy Bill.

Dipper leaned back against his pillows, Bill practically climbing on top of him as he thrust his tongue into Dipper's mouth, tasting him thoroughly. His wandering hands dropped to Dipper's chunky thighs, stroking them slowly, and Dipper shivered at the touch. Bill's warmth seeped right through his clothes and skin, all the way down to his marrow, heating him up from the inside.

Bill actually listened to what he said. He actually talked back with the same intelligence as Dipper himself, if not more. _Definitely_ more. While with Bill, Dipper found himself laughing more, smiling more, and the warmth that bubbled in the pit of his stomach had become intoxicating. Dipper had never felt like this before, not that he had ever had the chance, either, however.

Bill's claws dug into the fat of Dipper's thighs, not piercing his clothes or skin, but it sent an electric jolt up Dipper's spine. Bill fell between Dipper's thighs, and without thinking, Dipper wrapped his legs around Bill's sculpted waist.

Dipper's hands wandered up from Bill's shoulders, brushing the back of his neck as he tangled his fingers in Bill's long, blue and black hair. When Dipper tugged at Bill's hair, Bill released a pleasured moan into Dipper's mouth, his golden eyes flying open.

Dipper panted, staring at Bill through heavy eyes. With Bill's mouth open wide, Dipper could see his double row of shark-like teeth, a couple of them capped gold. How inhuman.

Though their date could barely classify a date, when Bill took Dipper back home, both Dipper's parents were out. Most likely, trying to escape having to deal with Bill. It seemed no matter _how_ much Dipper had told them that Bill's looks didn't match his personality, they refused to see past his leather jacket, dyed hair, and the triangular scar that split over his nose which connected to his tattooed "third eye" on his forehead.

Dipper had tried convincing them that Bill was of a different faith, chakras and the "third eye" and all that, but they didn't seem to believe him. Dipper didn't blame them. Still, without his parents hanging over him and Bill, the had been able to have a nice dinner before Bill had suggested they go upstairs to his room.

Dipper couldn't possibly say no to that.

Dipper squirmed. Fire coursed through his veins, flushing his skin. With that fire, however, came an onset of panic as well.

Bill tugged at his flannel, popping out the first two buttons, displaying his hairy chest. Thin hips pressed up between his legs, and the thick fabric of Dipper's jeans couldn't prevent him from feeling the ghost of Bill's obvious bulge.

Dipper's hands slipped from the back of Bill's head, and he pushed Bill away firmly by the chest.

"B- Bill…." Dipper gasped, hate boiling in him at how pitched his unsteady voice had become. He gulped thickly, shaking his head, and peered up at Bill uncertainly, a little tingle of fear teasing his heartstrings as his eyes met Bill's.

Despite his dark skin, Bill's flush still shone brilliantly on his cheeks, and his eyes were dilated and blown wide. His shoulders trembled with hungry, breathy pants, and yet his parted mouth was already beginning to tug into a frown.

Bill pulled back carefully, his eyes becoming calculating, if not a little curious, once more. "P- Pine Tree? What's wrong?"

Dipper bit the inside of his cheek, mulling over his uncertain words like wine that had long turned into vinegar. Staring up into Bill's face, the sudden fear of _disappointing_ him struck Dipper like lightening. "I- I-" Dipper shook his head, looking away. "I just… this is all new to me, is all," he admitted with an embarrassed whisper. The flush that smothered his skin was no longer from Bill's heat. "I've never…." Dipper shifted his legs, bumping his thighs against Bill's. "You know. Have had sex?" His voice cracked again.

Bill cocked his head to the side, straightened up, then leaned back on his haunches. "You- you haven't?"

Dipper shook his head, his eyes falling downcast. "Well… no. I- I mean. I've never even dated anyone. Not- not really. So of course I wouldn't have had…."

Bill shrugged. "You don't have to be in a relationship to have sex." Maneuvering his body, Bill went to straddle one of Dipper's legs before laying down besides him, wrapping his arms tight around Dipper. "But I mean… it's not that big of a deal if you haven't, kid."

Dipper dared to glance at Bill, a little surprise etched into his face. "Really? But… you want to…."

Bill shrugged. "Yeah? So? There are plenty of people who haven't had sex! Plenty of people who aren't interested in it to begin with! Besides, it just means I get you _all_ to myself and don't have any competition!" A sharp grin split Bill's face in two.

Dipper squeaked, his entire body becoming painted with his blush. "B- Bill…."

Bill pressed a hot, open-mouthed kiss to Dipper's cheek. He gripped Dipper's jaw, holding him steady as his lips explored Dipper's face. Once Bill discovered Dipper's lips, he stole yet another kiss from him.

Dipper gasped, kissing back until breathless once more, then pulled back, his eyes blown. "Are- are we really going to- going to…?"

Bill rolled over Dipper, straddling his lap, and pressed his hands against the bed either side of Dipper's head. "That was the plan, Pine Tree." Before Dipper could answer, Bill rolled his hips against Dipper's, making him keen.

"S- So you- you don't care that- that I'm a- a virgin…?"

Bill snorted, but his grin somehow grew wider. "I'm going to be honest with ya, kid, the fact that you're a virgin is a major turn on for me, and all this talkin' about it is _really_ making me in the mood to fuck your brains out."

Dipper gasped. "B- Bill!" he practically screeched as Bill went to nip and lick at Dipper's neck.

"What? It's true!" Bill rumbled against his skin. "God, you really are a fucking turn on, ya know?" Bill's hands pressed underneath Dipper's shirt, gripping at his plush sides. "Everything about you is wonderful, and I want to _drown_ in your body." Bill attacked Dipper's neck with more fervor, pulling another cry from him.

Dipper found himself hanging onto Bill for dear life as Bill continued to press down against him, his chest rumbling oddly with need. Even if Dipper _wanted_ to fight the sensations searing beneath his skin, peeling him inside out, and baring him fully, he couldn't.

Dipper arched up into Bill, gasping, and rocked his hips up against Bill's, thrusting against him in time with the hard bites Bill littered the base of his neck with.

A growl- an actual _growl-_ escaped Bill, and he thrusted back against Dipper just as hard. Though Dipper wore thick denim jeans, there was no denying the pressure built up between his legs.

Nor was there denying the already obvious bulge in Bill's pants either.

Clamping down on the nerves boiling in his stomach, Dipper shoved Bill back, briefly taking the reins from Bill.

Bill grinned down at Dipper, holding still, curious to see what he would do.

But Dipper didn't throw himself into Bill's arms, as Bill was expecting. Nor did he attack him with kisses just as hot and needy as his own.

No, once again, Dipper surprised Bill by going straight to his pants. He popped out the button and unzipped the zipper. Despite the shaking of his hands, he managed to get Bill's pants down in record time.

Bill groaned, staring down at how close Dipper's hands were to his still clothed cock. His tongue darted out to lap at his lips, and the fire that had been searing his innermost core seemed to push up, right against the underside of his skin.

Bill grabbed Dipper's shoulders and dragged him into another drawn out kiss just as the fire pushed out of his body, setting his entire body aflame. A brief spark of pain encircled his forehead, and before Bill knew what was happening, Dipper was ripping himself away from him, his eyes wide, staring at the space just above his head.

Bill's eyes fluttered open. "Pine Tree…?" With a frown tugging at his lips, Bill followed Dipper's gaze, and reached up to caress one of the smooth, black horns curving out of his forehead. "Oh. Oops. Um, I forgot to mention it earlier, but I'm a demon. Uh… now you know?"

Dipper continued to stare at Bill with enormous eyes, his lips pressed into a line.

"Kid? You- you okay?" Bill reached out to touch Dipper's face, but thought better of it, and dropped his hand. He cursed low under his breath. "This always happens. I- I lose control of my, uh, body when I am… in the process of, uh, losing control of my dick…." Bill rubbed his red face with the palm of his hand. "This revelation didn't make you catatonic, did it?" Bill cursed again, pulling fully away from Dipper. His cock still throbbed painfully, but there was nothing Bill could do about it right now.

"Fuck," Bill hissed. "Outta all the meatsacks I've met, I thought you out of all of em would unders-"

"I was right!" Dipper proclaimed, startling Bill. Not that he'd ever admit that, of course.

"W- What?" Bill spluttered. Much to his shock, Dipper leaned up as well, grabbing his hands. Dipper's grin was as blinding as it was stunning.

"I was right!" Dipper repeated. "You're not human at all! I- I guess I shoulda figured demon…." Dipper flushed brightly. "Especially since that's, well, my specialization… but books can only go so far! But demon! I was thinking some form of vampire for a while, or maybe incubus? But this is even better!"

"Wait, you seriously thought I was a vampire?!" Bill shook his head, tucking that fact away to be dealt with later. "Kid! What the fuck! You _knew_ I wasn't human this whole time and never asked?"

Dipper snorted. "Of course I knew you weren't human! You have pointed ears, golden eyes, _two rows of fangs,_ and that blue hair can't possibly be dyed. I never see your roots!" Dipper shook his head, crossing his arms. "I knew you weren't human from the beginning."

Bill pouted himself, pressing his hands between his legs. His boner was finally starting to calm down. Lovely. "If you knew this _entire_ time, why didn't you ask me what I was?"

"I thought about doing so, but Mabel told me doing that would be rude! And besides, you never shut up about anything ever, so I figured you'd tell me eventually."

Bill made an offended noise. "That's not true!"

"Is too!"

"Is _not!"_ Bill crossed his arms, his boner finally dead, and leaned back on his haunches. "So you really knew. This whole entire time. I wasted my time wondering how'd I tell you about my species this entire time?"

Dipper hummed. "Yup! Basically, when you put it that way. But I thought time wasn't real?" Dipper wiggled his eyebrows and smirked at Bill.

Bill threw his hands up into the air. His horns disappeared. "You! It's not!" Bill hopped off the bed and begun to pace, and Dipper barked a laugh and scooted to the edge of the bed.

"Hey, come back here." Dipper held out his leg to try and trip Bill up, but the demon merely stepped over his foot. "Stop being a baby. So what if I kinda already had an idea? Least I wasn't clueless and started running screaming."

Bill snorted. "Even if you did had an idea, you'd never do that. One of the reasons why I like ya, kid."

Dipper blushed lightly. "Exactly. So come back over here. I miss you already."

Bill groaned, but a slight smile tugged at his lips, and he went to sit back down besides Dipper. "Better?"

Dipper leaned against Bill. Bill went to wrap an arm around him. "Much. So… are- are we good now?"

Bill sighed. "We've always been good, Pine Tree." Bill kissed his cheek, and rubbed his shoulder. "But now that you got confirmation on what I am, are you going to be asking me inane questions every other minute?"

Dipper's cheeks flamed. "Hey! I don't ask inane questions!"

Bill quirked a brow. "Well?"

Dipper sighed, looking away. "Well, I- I may have been making a little _list…_ but now that I _know_ what you are, I'm gonna have to go and fix it!"

Bill couldn't help it; he burst out laughing at the enthusiasm in Dipper's voice. "How about this, kid, I'll go get us some ice cream, since it kinda sounds good right now, and you start fixing up that list. And perhaps we could continue our, ah, fun from before, later tonight?" Bill trailed the tips of his fingers across Dipper's back, making him shudder, a soft moan threatening to break his lips.

Dipper grinned at Bill, eyes sparkling. "Sounds like a plan."

**Author's Note:**

> This was short, but I had fun writing it all the same.  
> There are two sequels to this already as well- "Bill's Husband" and "A Date with a Demon's Husband" if any of y'all are interested!  
> Thanks for reading! Comments and kudos are appreciated!


End file.
